Fluorine respiratory toxicity

Upper respiratory toxicants include hydrogen halides (hydrogen chloride, hydrogen bromide), oxides (nitrogen oxides, sulfur oxides, sodium oxide), and hydroxides (ammonium hydroxide, sodium dusts, and potassium hydroxides). Lower respiratory toxicants include monomers (such as acrylonitrile), halides (fluorine, chlorine, bromine), and other miscellaneous... 

Toxicity. Fluorine is extremely corrosive and irritating to the skin. Inhalation at even low concentrations irritates the respiratory tract at high concentrations fluorine inhalation may result in severe lung congestion. 

The toxicity of fluoroacetic acid and of its derivatives has played an historical decisive role at the conceptual level. Indeed, it demonstrates that a fluorinated analogue of a natural substrate could have an activity profile that is far different from that of the nonfluorinated parent compound. The toxicity of fluoroacetic acid is due to its ability to block the citric acid cycle (Krebs cycle), which is an essential process of the respiratory chain. The fluoroacetate is transformed in vivo into 2-fluorocitrate by the citrate synthase. It is generally admitted that aconitase (the enzyme that performs the following step of the Krebs cycle) is inhibited by 2-fluorocitrate the formation of aconitate through elimination of the water molecule is a priori impossible from this substrate analogue (Figure 7.1). 

The immediate cause of death seems to be the result of a paralytic action on the central nervous system, particularly on the respiratory centre. Typical toxic signs of poisoning by fluorine-containing silatranes are hyperexcitation, muscle twitching, spasm of abdominal muscles, tremor, salivation. 

The vapor irritates the eyes and respiratory system. The liquid burns the eyes and quickly penetrates the skin to cause deep-seated burns. Assumed to cause severe burning and damage if taken by mouth. There is no reported toxic effect due to the presence of fluorine, as in the case of highly toxic fluoroacetic acid. Avoid breathing vapor. Prevent contact with skin and eyes.1... 

Bromine is toxic when inhaled or ingested. Like chlorine and fluorine, it is an irritant to the respiratory tract and eyes because it attacks their mucous membranes. Pulmonary edema may result from severe bromine poisoning. The severely irritating nature of bromine causes a withdrawal response in its presence, thereby limiting exposure. 

In contrast to highly lipophilic compounds, hydrophilic toxicants characterized by higher water solubility, e.g. hydrogen chloride and fluorine, are primarily adsorbed by the wet mucosa membranes of the throat and trachea in the upper respiratory tract. This is also the primary area for G-agent first-order absorption according to higher water... 

USE Fluorinating agent. Caution Highly toxic and irri-liting to mucous membranes, skin, eyes, respiratory tract. 

Bromine pentafluoride is more active and toxic than elemental fluorine or bromine trifluoride. The liquid is severely corrosive to the skin. The vapors are highly irritating to the eyes, skin, and mucous membranes. Exposure to 500 ppm vapor caused gasping, swelling of eyelids, cloudiness of the cornea, lacrimation, salivation, and respiratory distress in test animals (ACGIH 1986). A few minutes exposure to 100 ppm was lethal to most experimental animals. Chronic exposure can cause nephrosis and hepatosis. Ingestion of a few drops can cause severe corrosion and bum the mouth. 

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